[GHC] #9791: Ghc panics on tiny example, naive try to overload compose

10 Nov 2014


      #9791: Ghc panics on tiny example, naive try to overload compose
-------------------------------------+-------------------------------------
       Reporter:  camarao            |                   Owner:
           Type:  bug                |                  Status:  new
       Priority:  normal             |               Milestone:
      Component:  Compiler           |                 Version:  7.4.1
       Keywords:  Overloading        |        Operating System:  Linux
   Architecture:  x86                |         Type of failure:  Compile-
     Difficulty:  Easy (less than 1  |  time crash
  hour)                              |               Test Case:
     Blocked By:                     |                Blocking:
Related Tickets:                     |  Differential Revisions:
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 {-# LANGUAGE MultiParamTypeClasses #-}

 class Compose a b c e f where
   (<.>)::(b -> c)->(a -> e)->(a -> f)

 instance Compose a b c b c where
   (<.>) = (.)

 instance Monad m -> Compose a b c (m b) (m c) where
   (<.>) f g a = g a >>= (return . f)

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Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9791
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